It is known that a brake pad is a vehicle wheel braking element intended for interacting with either the disc or drum brake of the wheel, and comprises a metal support, known as “backplate”, a block of friction material, which is molded in its entirety onto one side of the metal support, and an isolating/damping layer arranged between the block of friction material and the metal support which is referred to by the term “underlayer”.
The metal support is commonly made of steel or cast iron, since in use it must withstand both considerable thermal and mechanical stresses. However, steel supports and, in general, those of a iron material, have the dual disadvantage of being subject to corrosion, therefore they require adequate protection treatments, and have a relatively high weight. The growing demand in the “Automotive” field for weight reduction and increased performance, for example corrosion resistance, has prompted research into the use of alternative materials such as plastics/composites rather than light alloys such as aluminum alloys, as it is known from JP9126258.
Unfortunately, mechanical and/or thermo-mechanical strength problems associated with these materials have so far prevented their use, since they are not suitable for high-temperature and high-stress applications.
It is, for example, known that common aluminium alloys lose important mechanical properties such as tensile strength and yield strength when subjected to thermal cycling, at temperatures normally achieved during the brake pad manufacturing processes, rather than when they are used on a vehicle.